Dicing-tape integrated film for backside of semiconductor and method of manufacturing semiconductor device

ABSTRACT

The present invention is to provide a dicing-tape integrated film for the backside of a semiconductor that is capable of suppressing the transfer of the coloring agent contained in a film for the backside of a flip-chip semiconductor formed on the pressure-sensitive adhesive layer of the dicing tape onto the dicing tape. The dicing-tape integrated film for the backside of a semiconductor has a dicing tape having a substrate and a pressure-sensitive adhesive layer formed on the substrate and a film for the backside of a flip-chip semiconductor formed on the pressure-sensitive adhesive layer of the dicing tape, the film for the backside of a flip-chip semiconductor contains a coloring agent, and the solubility of the coloring agent to toluene at 23° C. is 2 g/100 ml or less.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a dicing-tape integrated film for thebackside of a semiconductor and a method of manufacturing asemiconductor device.

2. Description of the Related Art

In recent years, thinning and downsizing of a semiconductor device andits packaging have been further required. Because of that, a flip-chipsemiconductor device, in which a semiconductor element such as asemiconductor chip is flip-chip bonded on a substrate, has been widelyused as a semiconductor device and its packaging. In the flip-chipbonding, a circuit surface of a semiconductor chip is fixed to anelectrode forming surface of the substrate in a way that the circuitsurface is facing to the electrode forming surface. In suchsemiconductor device, etc., the backside of the semiconductor chip maybe protected by a film for the backside of a flip-chip semiconductor toprevent the semiconductor chip from damage, etc.

Various information (for example, character information and graphicinformation) such as an identification number of a semiconductor chipmay be printed on the film for the backside of a flip-chip semiconductorby laser marking. Because of that, a coloring agent is added to the filmfor the backside of a flip-chip semiconductor.

Conventionally, there has been a dicing-tape integrated film for thebackside of a semiconductor in which a film for the backside of aflip-chip semiconductor is integrally pasted on a dicing tape (forexample, refer to Patent Document 1).

PRIOR ART DOCUMENT Patent Document

Patent Document 1: JP-B-5456440

SUMMARY OF THE INVENTION

However, in the film for the backside of a dicing-tape integratedsemiconductor, there is a problem that the coloring agent in the filmfor the backside of a flip-chip semiconductor is transferred onto thedicing tape due to heating, etc. when a wafer is pasted to the film forthe backside of a flip-chip semiconductor. Especially, when lasermarking is performed to the film for the backside of a flip-chipsemiconductor by irradiating the film with a laser beam from thedicing-tape side while the film is still a dicing-tape integrated filmfor the backside of a semiconductor, there is a problem that the laserbeam is blocked by the coloring agent transferred onto the dicing tape,the laser beam does not reach to the film for the backside of aflip-chop semiconductor, and laser marking cannot be preferablyperformed.

The present inventors have investigated a dicing-tape integrated filmfor the backside of a semiconductor to solve the above-described problempoints. As a result, it was found that the transfer of the coloringagent contained in a film for the backside of a flip-chip semiconductoronto the dicing tape can be suppressed by adopting the followingconfiguration, and the present invention has been completed.

That is, the dicing-tape integrated film for the backside of asemiconductor has a dicing tape having a substrate and apressure-sensitive adhesive layer formed on the substrate and a film forthe backside of a flip-chip semiconductor formed on thepressure-sensitive adhesive layer of the dicing tape, and ischaracterized in that the film for the backside of a flip-chipsemiconductor contains a coloring agent, and the solubility of thecoloring agent to toluene at 23° C. is 2 g/100 ml or less.

Because the film for the backside of a flip-chip semiconductor isprovided on the backside of a semiconductor element generating heat,heat resistance becomes necessary. Because of that, the film for thebackside of a flip-chip semiconductor is formed of a material capable ofproviding heat resistance, and the material capable of providing heatresistance normally has high polarity. On the other hand, heatresistance is not required for the pressure-sensitive adhesive layer ofthe dicing tape, it is not necessary for the layer to contain a materialcapable of providing heat resistance, and the layer normally has lowpolarity.

Toluene is a solvent having relatively low polarity. Therefore, thecoloring agent having low solubility to toluene is considered to haverelatively high polarity.

In the present invention, the coloring agent having relatively highpolarity in which its solubility to toluene at 23° C. is 2 g/100 ml orless is contained to the film for the backside of a flip-chipsemiconductor having high polarity. As a result, the coloring agent canbe retained in the film for the backside of a flip-chip semiconductor,and the transfer of the coloring agent onto the pressure-sensitive layercan be suppressed.

In the above-described configuration, the coloring agent preferablycontains an anthraquinone skeleton. Generally, the solubility of amolecule having a plurality of benzene rings to a solvent becomes lowdue to overlapping of the molecules. Because the anthraquinone skeletonhas a structure in which cyclohexane is sandwiched by two benzene rings,a solvent enters between the molecules to a moderate degree compared topigments such as phthalocyanine. As a result, the solubility to asolvent can be maintained. On the other hand, because the solubility totoluene is low, the transfer of the coloring agent onto thepressure-sensitive adhesive layer can be suppressed. That is, thecoloring agent having an anthraquinone skeleton has an excellent balancebetween the solubility to a solvent and the suppression of transfer ontothe pressure-sensitive adhesive layer. This is clear from examples.

In the above-described configuration, a difference between the surfacefree energy E1 of the film for the backside of a flip-chip semiconductorand the surface free energy E2 of the pressure-sensitive adhesive layer(E1-E2) is preferably 10 mJ/m² or more.

When the difference (E1-E2) is 10 mJ/m² or more, the transfer of thecoloring agent onto the pressure-sensitive adhesive layer can be morepreferably suppressed.

The method of manufacturing a semiconductor device according to thepresent invention is a method of manufacturing a semiconductor deviceusing the dicing-tape integrated film for the backside of asemiconductor described above, and characterized to have

a step A of pasting a semiconductor wafer on a film for the backside ofa flip-chip semiconductor in the dicing-tape integrated film for thebackside of a semiconductor,

a step B of performing laser marking to the film for the backside of aflip-chip semiconductor from the dicing tape side after the step A,

a step C of dicing the semiconductor wafer to form a semiconductorelement,

a step D of peeling the semiconductor element from thepressure-sensitive adhesive layer together with the film for thebackside of a flip-chip semiconductor, and

a step E of flip-chip bonding the semiconductor element on an adherend.

According to the above-described configuration, transfer of the coloringagent in the film for the backside of a flip-chip semiconductor issuppressed. Therefore, a situation hardly occurs in which the laser beamis blocked in the pressure-sensitive adhesive layer in the step B ofperforming laser marking and the laser beam does not reach to the filmfor the backside of a flip-chip semiconductor. As a result, asemiconductor device can be obtained in which laser marking ispreferably performed on the film for the backside of a flip-chipsemiconductor.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic cross-sectional view showing one example of thedicing-tape integrated film for the backside of a semiconductoraccording to one embodiment of the present invention; and

FIGS. 2( a) to 2(e) are schematic cross-sectional views showing oneexample of the method of manufacturing a semiconductor device using thedicing-tape integrated film for the backside of a semiconductoraccording to one embodiment of the preset invention.

Specifically, FIG. 2( a) is a view showing mounting step.

FIG. 2( b) is a view showing laser marking step.

FIG. 2( c) is a view showing dicing step.

FIG. 2( d) is a view showing pickup step.

FIG. 2( e) is a view showing flip-chip connecting step.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

(Dicing-tape Integrated Film for the Backside of a Semiconductor)

The dicing-tape integrated film for the backside for a semiconductoraccording to one embodiment of the present invention is explained belowwhile referring to the drawings. FIG. 1 is a schematic cross-sectionalview showing one example of the dicing-tape integrated film for thebackside of a semiconductor according to one embodiment of the presentinvention. As shown in FIG. 1, a dicing-tape integrated film 1 for thebackside of a semiconductor has a configuration having a dicing tape 2in which a pressure-sensitive adhesive layer 22 is provided on asubstrate 21 and a film 40 for the backside of a flip-chip semiconductor(referred to as “a film 40 for the backside of a semiconductor, below).As shown in FIG. 1, the dicing-tape integrated film for the backside ofa semiconductor of the present invention may have a configuration inwhich the film 40 for the backside of a flip-chip semiconductor isformed only on a portion 23 corresponding to a pasting portion of asemiconductor wafer on the pressure-sensitive adhesive layer 22 of thedicing tape 2. However, it may have a configuration in which the filmfor the backside of a semiconductor is formed on the entire surface ofthe pressure-sensitive adhesive layer or it may have a configuration inwhich the film for the backside of a semiconductor is formed on aportion larger than the portion corresponding to the pasting portion ofa semiconductor wafer and smaller than the entire surface of thepressure-sensitive adhesive layer. Further, the surface of the film forthe backside of a semiconductor (the surface that is pasted to thebackside of a wafer) may be protected by a separator, etc. until it ispasted to the backside of a wafer.

(Film for the Backside of a Flip-Chip Semiconductor)

cis preferably formed by containing a thermosetting resin and athermoplastic resin.

Examples of the thermoplastic resin include a natural rubber, a butylrubber, an isoprene rubber, a chloroprene rubber, an ethylene-vinylacetate copolymer, an ethylene-acrylate copolymer, an ethylene-acrylicester copolymer, a polybutadiene resin, a polycarbonate resin, athermoplastic polyimide resin, polyamide resins such as 6-nylon and6,6-nylon, a phenoxy resin, an acrylic resin, saturated polyester resinssuch as PET (polyethylene terephthalate) and PBT (polybutyleneterephthalate), a polyamideimide resin, and a fluororesin. Thethermoplastic resins can be used alone or two types or more can be usedtogether. Of these thermoplastic resins, acrylic resin is particularlypreferable since the resin contains ionic impurities in only a smallamount and has a high heat resistance so as to make it possible toensure the reliability of the semiconductor element.

The acrylic resin is not especially limited, and examples thereofinclude a polymer having one type or two types or more of acrylates ormethacrylates having a linear or branched alkyl group having 30 or lesscarbon atoms (preferably 4 to 18 carbon atoms, further preferably 6 to10 carbon atoms, and especially preferably 8 or 9 carbon atoms) as acomponent. That is, the acrylic resin of the present invention has abroad meaning and also includes a methacrylic resin. Examples of thealkyl group include a methyl group, an ethyl group, a propyl group, anisopropyl group, an n-butyl group, a t-butyl group, an isobutyl group, apentyl group, an isopentyl group, a hexyl group, a heptyl group, a2-ethylhexyl group, an octyl group, an isooctyl group, a nonyl group, anisononyl group, a decyl group, an isodecyl group, an undecyl group, adodecyl group (a lauryl group), a tridecyl group, a tetradecyl group, astearyl group, and an octadecyl group.

Other monomers that can form the above-described acrylic resin (monomersother than an alkylester of acrylic acid or methacrylic acid having analkyl group having 30 or less carbon atoms) are not especially limited.Examples thereof include carboxyl-containing monomers such as acrylicacid, methacrylic acid, carboxyethyl acrylate, carboxypentyl acrylate,itaconic acid, maleic acid, fumaric acid, and crotonic acid; acidanhydride monomers such as maleic anhydride and itaconic anhydride;hydroxyl-containing monomers such as 2-hydroxyethyl(meth)acrylate,2-hydroxypropyl(meth)acrylate,4-hydroxybutyl(meth)acrylate,6-hydroxyhexyl(meth)acrylate,8-hydroxyoctyl(meth)acrylate, 10-hydroxydecyl(meth)acrylate,12-hydroxylauryl(meth)acrylate, and(4-hydroxymethylcyclohexyl)methylacrylate; monomers which contain asulfonic acid group, such as styrenesulfonic acid, allylsulfonic acid,2-(meth)acrylamide-2-methylpropanesulfonic acid, (meth)acrylamidepropanesulfonic acid, sulfopropyl(meth)acrylate, and(meth)acryloyloxynaphthalenesulfonic acid; and monomers which contain aphosphoric acid group, such as 2-hydroxyethylacryloyl phosphate. Amongthese, a carboxyl group-containing monomer is preferable from theviewpoint that the tensile storage modulus Ea of the die bond film canbe set at a preferred value. (Meth)acrylate refers to an acrylate and/ora methacrylate, and every “(meth)” in the present invention has the samemeaning.

Among these, an acrylic resin is preferable that is formed from amaterial containing acrylonitrile, acryloyl morpholine, etc. as monomercomponents from a viewpoint of improving the heat resistance of the film40 for the backside of a semiconductor.

When the SP value (a solubility parameter) of the thermoplastic resincontained in the film 40 for the backside of a semiconductor isrepresented by SP1 and the SP value of the base polymer constituting thepressure-sensitive adhesive layer 22 is represented by SP2, among theabove-described thermoplastic resins, the thermoplastic resin containedin the film 40 for the backside of a semiconductor preferably has the SPvalue (SP1) of 16 to 10, and more preferably has the SP value (SP1) of14 to 11 as long as a relationship of (SP1)>(SP2) is satisfied. When thethermoplastic resin having the SP value (SP1) of 10 or more is used, thepolarity of the film becomes close to that of the coloring agent havingthe solubility to toluene at 23° C. of 2 g/100 ml or less. Therefore,the coloring agent having the solubility to toluene at 23° C. of 2 g/100ml or less can be preferably retained in the film 40 for the backside ofa semiconductor, and the transfer onto the pressure-sensitive adhesivelayer 22 can be suppressed.

The SP value (SP1) of the thermoplastic resin contained in the film 40for the backside of a semiconductor can be controlled by appropriatelyselecting the monomer components when forming the film 40 for thebackside of a semiconductor.

The SP1 and the SP2 preferably satisfy the relationship of (SP1)>(SP2),and a difference between the SP1 and the SP2 is preferably 1 or more.The difference is more preferably 2 or more. When the difference is 1 ormore, the transfer of the coloring agent in the film 40 for the backsideof a semiconductor onto the pressure-sensitive adhesive layer 22 can bepreferably suppressed. In addition, peeling of the film 40 for thebackside of a semiconductor and the pressure-sensitive adhesive layer 22becomes easy in a pickup step.

When two types or more of the thermoplastic resins and/or the basepolymers are contained, the difference is the minimum difference betweenthe SP1 and the SP2 of any pair of the thermoplastic resins and the basepolymers.

The SP value of the polymer is measured with methods of measuring theintrinsic viscosity of the polymer, measuring the suspension point whena nonsolvent is dropped in a dilute solution of the polymer, measuringthe maximum swelling ratio in various solvents of the polymer, etc. Inthe present description, the SP value of the thermoplastic resin (forexample, an acrylic resin) is calculated according to a method describedin Fedors, Polym. Eng. And Sci., 14:147 (1974).

As described later, the base polymer constituting the pressure-sensitiveadhesive layer 22 preferably has the SP value (SP2) of 13 to 7, and morepreferably has the SP value (SP2) of 12 to 8 as long as a relationshipof (SP1)>(SP2) is satisfied. When the base polymer having the SP value(SP2) of 13 or less is used, the coloring agent is hardly transferred.Further, a large difference between the SP value (SP2) and the SP value(SP1) of the thermoplastic resin contained in the film 40 for thebackside of a semiconductor can be easily obtained. As a result, peelingof the film 40 for the backside of a semiconductor and thepressure-sensitive adhesive layer 22 becomes easy in a pickup step.

Examples of the thermosetting resin include an epoxy resin, a phenolresin, an amino resin, an unsaturated polyester resin, a polyurethaneresin, a silicone resin, and a thermosetting polyimide resin. Thethermosetting resins can be used alone or two types or more can be usedtogether. An epoxy resin having a small amount of ionic impurities thaterode the semiconductor element is especially suitable as thethermosetting resin. Further, a phenol resin can be suitably used as acuring agent for the epoxy resin.

The epoxy resin is not especially limited, and examples thereof includebifunctional epoxy resins and polyfunctional epoxy resins such as abisphenol A type epoxy resin, a bisphenol F type epoxy resin, abisphenol S type epoxy resin, a brominated bisphenol A type epoxy resin,a hydrogenated bisphenol A type epoxy resin, a bisphenol AF type epoxyresin, a bisphenyl type epoxy resin, a naphthalene type epoxy resin, afluorene type epoxy resin, a phenol novolak type epoxy resin, anortho-cresol novolak type epoxy resin, a trishydroxyphenylmethane typeepoxy resin, and a tetraphenylolethane type epoxy resin, a hydantointype epoxy resin, a trisglycidylisocyanurate type epoxy resin, and aglycidylamine type epoxy resin.

Among the above-described epoxy resins, a novolak type epoxy resin, abiphenyl type epoxy resin, a trishydroxyphenylmethane type epoxy resin,and a tetraphenylolethane type epoxy resin are especially preferable.These epoxy resins are highly reactive with a phenol resin as a curingagent and are excellent in heat resistance.

The phenol resin acts as a curing agent for the epoxy resin, andexamples thereof include novolak type phenol resins such as a phenolnovolak resin, a phenol aralkyl resin, a cresol novolak resin, atert-butylphenol novolak resin, and a nonylphenol novolak resin, a resoltype phenol resin, and polyoxystyrenes such as polyparaoxystyrene. Thephenol resins can be used alone or two types or more can be usedtogether. Among these phenol resins, a phenol novolak resin and a phenolaralkyl resin are especially preferable because connection reliabilityof the c can be improved.

The phenol resin is suitably compounded in the epoxy resin so that ahydroxyl group in the phenol resin to 1 equivalent of an epoxy group inthe epoxy resin component becomes 0.5 to 2.0 equivalents. The ratio ismore preferably 0.8 to 1.2 equivalents. When the compounding ratio goesout of this range, sufficient curing reaction does not proceed, and thecharacteristics of the epoxy resin cured substance easily deteriorate.

A thermal curing accelerating catalyst for an epoxy resin and a phenolresin may be used in the present invention. The thermal curingaccelerating catalyst is not especially limited, and the catalyst can beappropriately selected from known thermal curing accelerating catalysts.The thermal curing accelerating catalysts can be used alone or two typesor more can be used together. Examples of the thermal curingaccelerating catalyst include an amine curing accelerator, a phosphoruscuring accelerator, an imidazole curing accelerator, a boron curingaccelerator and a phosphorus-boron curing accelerator.

The film 40 for the backside of a semiconductor are suitably formed of aresin composition containing an epoxy resin and a phenol resin and aresin composition containing an epoxy resin, a phenol resin, and anacrylic resin. Because these resins have few ionic impurities and highheat resistance, reliability of the semiconductor element can beensured.

It is important that the film 40 for the backside of a semiconductor hastackiness (adhesion) to the backside (the surface where a circuit is notformed) of a semiconductor wafer. The film 40 for the backside of asemiconductor can be formed of a resin composition containing an epoxyresin as a thermosetting resin, for example. A polyfunctional compoundthat reacts with a functional group of the end of the polymer molecularchain is preferably added as a crosslinking agent to crosslink the film40 for the backside of a semiconductor to some extent in advance. Withthis operation, the adhesion characteristics under high temperature canbe improved and the heat resistance can be improved.

The crosslinking agent is not especially limited, and a knowncrosslinking agent can be used. Specific examples thereof include anisocyanate crosslinking agent, an epoxy crosslinking agent, a melaminecrosslinking agent, a peroxide crosslinking agent, a urea crosslinkingagent, a metal alkoxide crosslinking agent, a metal chelate crosslinkingagent, a metal salt crosslinking agent, a carbodiimide crosslinkingagent, an oxazoline crosslinking agent, an aziridine crosslinking agent,and an amine crosslinking agent. An isocyanate crosslinking agent and anepoxy crosslinking agent are preferable. The crosslinking agents can beused alone or two type or more can be used together.

Examples of the isocyanate crosslinking agent include lower aliphaticpolyisocyanates such as 1,2-ethylene diisocyanate, 1,4-butyleneisocyanate, and 1,6-hexamethylene diisocyanate; alicyclicpolyisocyanatessuch as cyclopentylene diisocyanate, cyclohexylene diisocyanate,isophorone diisocyanate, hydrogenated tolylene diisocyanate, andhydrogenated xylene diisocyanate; and aromatic polyisocyanates such as2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate,4,4′-diphenylmethane diisocyanate, and xylylene diisiocyanate. Atrimethylolpropane/tolylene diisocyanate trimer adduct (tradename:Coronate L manufactured by Nippon Polyurethane Industry Co., Ltd.) and atrimethylolpropane/hexamethylene diisocyanate trimer adduct (tradename:Coronate HL manufactured by Nippon Polyurethane Industry Co., Ltd.) canalso be used. Examples of the epoxy crosslinking agent includeN,N,N′,N′-tetraglycidyl-m-xylenediamine, diglycidylaniline,1,3-bis(N,N-glycidylaminomethyl)cyclohexane, 1,6-hexanedioldiglycidylether, neopentylglycol diglycidylether, ethyleneglycoldiglycidylether, propyleneglycol diglycidylether, polyethyleneglycoldiglycidylether, polypropyleneglycol diglycidylether, sorbitolpolyglycidylether, glycerol polyglycidylether, pentaerythritolpolyglycidylether, polyglyserol polyglycidylether, sorbitanpolyglycidylether, trimethylolpropane polyglycidylether, diglycidyladipate, diglycidyl o-phthalate,triglycidyl-tris(2-hydroxyethyl)isocyanurate, resorcin diglycidylether,bisphenol-s-diglycidyl ether, and an epoxy resin having two or moreepoxy groups in the molecule.

The used amount of the crosslinking agent is not especially limited, andcan be appropriately selected according to the level of crosslinking.Specifically, the used amount of the crosslinking agent is normallypreferably 7 parts by weight or less (0.05 to 7 parts by weight, forexample) to 100 parts by weight of a polymer component (especially, apolymer having a functional group at the end of the molecular chain) forexample. When the used amount of the crosslinking agent is more than 7parts by weight to 100 parts by weight of the polymer component, it isnot preferable because the adhering strength decreases. From theviewpoint of improving cohesive strength, the used amount of thecrosslinking agent is preferably 0.05 parts by weight or more to 100parts by weight of the polymer component.

In the present invention, it is possible to perform a crosslinkingtreatment by irradiation with an electron beam, an ultraviolet ray, orthe like in place of using the crosslinking agent or together with acrosslinking agent.

The film 40 for the backside of a semiconductor includes coloring agent.With this configuration, the films 40 for the backside of asemiconductor is colored and can exhibit an excellent marking propertyand an excellent appearance, and a semiconductor device can be obtainedhaving an appearance with added value. Because the colored film for thebackside of a semiconductor has an excellent marking property, variousinformation such as character information and pattern information can begiven to a semiconductor device or the surface where a circuit is notformed of the semiconductor device in which the semiconductor element ismarked through the film for the backside of a semiconductor usingvarious marking methods such as a printing method and a lasermarkingmethod. Especially, the information such as character informationand pattern information that is given by marking can be recognizedvisually with excellent visibility by controlling the color. Because thefilm for the backside of a semiconductor is colored, the dicing tape andthe film for the backside of a semiconductor can be easilydistinguished, and workability can be improved. It is possible tocolor-code the semiconductor device by product, for example. When thefilm for the backside of a semiconductor is colored (when it is notcolorless or transparent), the color is not especially limited. However,the color is preferably a dark color such as black, blue, or red, andblack is especially preferable.

In this embodiment, the dark color means a dark color having L* that isdefined in the L*a*b* color system of basically 60 or less (0 to 60),preferably 50 or less (0 to 50) and more preferably 40 or less (0 to40).

The black color means a blackish color having L* that is defined in theL*a*b* color system of basically 35 or less (0 to 35), preferably 30 orless (0 to 30) and more preferably 25 or less (0 to 25). In the blackcolor, each of a* and b* that is defined in the L*a*b* color system canbe appropriately selected according to the value of L*. For example,both of a* and b* are preferably −10 to 10, more preferably −5 to 5, andespecially preferably −3 to 3 (above all, 0 or almost 0).

In this embodiment, L*, a*, and b* that are defined in the L*a*b* colorsystem can be obtained by measurement using a colorimeter (tradename:CR-200 manufactured by Konica Minolta Holdings, Inc.). The L*a*b* colorsystem is a color space that is endorsed by Commission Internationale deI′Eclairage (CIE) in 1976, and means a color space that is called aCIE1976 (L*a*b*) color system. The L*a*b* color system is provided inJIS Z 8729 in the Japanese Industrial Standards.

A coloring agent corresponding to the desired color is used in the film40 for the backside of a semiconductor. The solubility of the coloringagent to toluene at 23° C. is 2 g/100 ml or less. The solubility ispreferably 1 g/100 ml or less, and more preferably 0.5 g/100 ml or less.Because the coloring agent having relatively high polarity in which itssolubility to toluene at 23° C. is 2 g/100 ml or less is contained inthe film 40 for the backside of a semiconductor having high polarity,the coloring agent can be retained in the film 40 for the backside of asemiconductor, and the transfer of the coloring agent onto thepressure-sensitive layer 22 can be suppressed.

The coloring agent is not especially limited as long as its solubilityto toluene at 23° C. is 2 g/100 ml or less, and various dark colormaterials such as black color materials, blue color materials, and redcolor materials can be preferably used, and black color materials areespecially preferable. The coloring agents include any of pigments,dyes, etc. The coloring agent may be used either alone or in combinationof two or more types. Further, the dyes can be used in any form of aciddyes, reactive dyes, direct dyes, disperse dyes, cationic dyes, etc.Further, the form of the pigments is not especially limited, and it canbe appropriately selected from the known pigments and used.

When dyes are used as the coloring agents, the films 40 for the backsideof a semiconductor (consequently a dicing-Tape Integrated Film 1 forBackside of Semiconductor) having uniform or almost uniform coloringconcentration can be easily manufactured because the dyes disperseuniformly or almost uniformly due to dissolution in the films 40 for thebackside of a semiconductor. Because of that, when the dyes are used asthe coloring agents, the coloring concentration of the film for thebackside of a semiconductor in the dicing tape-integrated film for thebackside of a semiconductor can be made uniform or almost uniform, andthe marking property and the appearance can be improved.

The black color material is not especially limited, and can beappropriately selected from inorganic black pigments and black dyes, forexample. The black color material may be a color material mixture inwhich a cyan color material (blue-green color material), a magenta colormaterial (red-purple color material), and a yellow color material aremixed together. The black color materials can be used alone or two typesor more can be used together. The black color materials can be used alsowith other color materials other than black.

Specific examples of the black color materials include carbon black suchas furnace black, channel black, acetylene black, thermal black, andlamp black, graphite (black lead), copper oxide, manganese dioxide, azopigments such as azomethine azo black, aniline black, perylene black,titaniumblack, cyanine black, activated carbon, ferrite such asnonmagnetic ferrite and magnetic ferrite, magnetite, chromium oxide,iron oxide, molybdenum disulfide, chromium complex, complex oxide black,and anthraquinone organic black.

In the present invention, black dyes such as C. I. solvent black 3, 7,22, 27, 29, 34, 43, and 70, C. I. direct black 17, 19, 22, 32, 38, 51,and 71, C. I. acid black 1, 2, 24, 26, 31, 48, 52, 107, 109, 110, 119,and 154, and C. I. disperse black 1, 3, 10, and 24; and black pigmentssuch as C. I. pigment black 1 and 7 can be used as the black colormaterial.

Examples of the coloring material in market having the solubility totoluene at 23° C. of 2 g/100 ml or less include a trade name“SOM-L-0543” manufactured by Orient Chemical Industries Co., Ltd., atrade name “ORIPACS B-1” manufactured by Orient Chemical Industries Co ., Ltd., and a trade name “SDO-7” manufactured by Arimoto Chemical Co.,Ltd.

Among the coloring agents described above, a coloring agent having ananthraquione skeleton is preferable. As examples indicate, when thecoloring agent has an anthraquione skeleton, the transfer of thecoloring agent onto the pressure-sensitive adhesive layer can bepreferably suppressed.

Examples of color materials other than the black color materials includea cyan color material, a magenta color material, and a yellow colormaterial . Examples of the cyan color material include cyan dyes such asC. I. solvent blue 25, 36, 60, 70, 93, and 95; and C. I. acid blue 6 and45; and cyan pigments such as C. I. pigment blue 1, 2, 3, 15, 15:1,15:2, 15:3, 15:4, 15:5, 15:6, 16, 17, 17:1, 18, 22, 25, 56, 60, 63, 65,and 66; C. I. vat blue 4 and 60; and C. I. pigment green 7.

Examples of the magenta color material include magenta dyes such as C.I. solvent red 1, 3, 8, 23, 24, 25, 27, 30, 49, 52, 58, 63, 81, 82, 83,84, 100, 109, 111, 121, and 122; C. I. disperse red 9; C. I. solventviolet 8, 13, 14, 21, and 27; C. I. disperse violet 1; C. I. basic red1, 2, 9, 12, 13, 14, 15, 17, 18, 22, 23, 24, 27, 29, 32, 34, 35, 36, 37,38, 39, and 40; and C. I. basic violet 1, 3, 7, 10, 14, 15, 21, 25, 26,27, and 28.

Examples of the magenta color material include magenta pigments such asC. I. pigment red 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16,17, 18, 19, 21, 22, 23, 30, 31, 32, 37, 38, 39, 40, 41, 42, 48:1, 48:2,48:3, 48:4, 49, 49:1, 50, 51, 52, 52:2, 53:1, 54, 55, 56, 57:1, 58, 60,60:1, 63, 63:1, 63:2, 64, 64:1, 67, 68, 81, 83, 87, 88, 89, 90, 92, 101,104, 105, 106, 108, 112, 114, 122, 123, 139, 144, 146, 147, 149, 150,151, 163, 166, 168, 170, 171, 172, 175, 176, 177, 178, 179, 184, 185,187, 190, 193, 202, 206, 207, 209, 219, 222, 224, 238, and 245; C. I.pigment violet 3, 9, 19, 23, 31, 32, 33, 36, 38, 43, and 50; and C. I.vat red 1, 2, 10, 13, 15, 23, 29, and 35.

Examples of the yellow color material include yellow dyes such as C. I.solvent yellow 19, 44, 77, 79, 81, 82, 93, 98, 103, 104, 112, and 162;and yellow pigments such as C. I. pigment orange 31 and 43, C. I.pigment yellow 1, 2, 3, 4, 5, 6, 7, 10, 11, 12, 13, 14, 15, 16, 17, 23,24, 34, 35, 37, 42, 53, 55, 65, 73, 74, 75, 81, 83, 93, 94, 95, 97, 98,100, 101, 104, 108, 109, 110, 113, 114, 116, 117, 120, 128, 129, 133,138, 139, 147, 150, 151, 153, 154, 155, 156, 167, 172, 173, 180, 185,and 195, and C. I. vat yellow 1, 3, and 20.

Various color materials such as cyan color materials, magenta colormaterials, and yellow color materials can be used alone or two types ormore can be used together. When two types or more of various colormaterials such as cyan color materials, magenta color materials, andyellow color materials are used, the mixing ratio or the compoundingratio of these color materials is not especially limited, and can beappropriately selected according to the types of each color material andthe intended color.

Other additives can be appropriately compounded in the film 40 for thebackside of a semiconductor as necessary. Examples of the otheradditives include a filler, a flame retardant, a silane coupling agent,an ion trapping agent, an extender, an anti-aging agent, an antioxidant,and a surfactant.

The filler may be any of an inorganic filler and an organic filler.However, an inorganic filler is preferable. By adding a filler such asan inorganic filler, electric conductivity can be given to the film 40for the backside of a semiconductor, heat conductivity can be improved,and the elastic modulus can be adjusted. The film 40 for the backside ofa semiconductor may be electrically conductive or non-conductive.Examples of the inorganic filler include ceramics such as silica, clay,gypsum, calcium carbonate, barium sulfate, alumina oxide, berylliumoxide, silicon carbide, and silicon nitride, metals such as aluminum,copper, silver, gold, nickel, chromium, lead, tin, zinc, palladium, andsolder, alloys, and various inorganic powders consisting of carbon. Thefillers may be used alone or two types or more can be used together.Among these, silica, especially molten silica is preferable. The averageparticle size of the inorganic filler is preferably in a range of 0.1 to80 μm. The average particle size of the inorganic filler can be measuredwith a laser diffraction type particle size distribution device, forexample.

The compounding amount of the filler (especially, the inorganic filler)is preferably 80 parts by weight or less (0 to 80 parts by weight), andespecially preferably 0 to 70 parts by weight to 100 parts by weight ofthe organic resin component.

Examples of the flame retardant include antimony trioxide, antimonypentoxide, and a brominated epoxy resin. These can be used alone or twotypes or more can be used together . Examples of the silane couplingagent include β-(3,4-epoxycyclohexyl) ethyltrimethoxysilane,γ-glycidoxypropyltrimethoxysilane, andγ-glycidoxypropylmethyldiethoxysilane. These compounds can be used aloneor two types or more can be used together . Examples of the ion trapagent include hydrotalcites and bismuth hydroxide. These can be usedalone or two types or more can be used together .

The film 40 for the backside of a semiconductor can be formed by acommon method of preparing a resin composition by mixing a thermosettingresin such as an epoxy resin, a thermoplastic resin such as an acrylicresin as necessary, and a solvent and other additives as necessary andforming the resin composition into a film-like layer.

When the film 40 for the backside of a semiconductor is formed of aresin composition containing a thermosetting resin such as an epoxyresin, the thermosetting resin in the film 40 for the backside of asemiconductor is uncured or is partially cured at the stage beforeapplication to a semiconductor wafer. In this case, the thermosettingresin in the film 40 for the backside of a semiconductor is completelycured or almost completely cured after application to a semiconductorwafer (normally when curing a sealing material in a flip-chip bondingstep).

Even if the film 40 for the backside of a semiconductor contains thethermosetting resin, since the thermosetting resin is uncured or ispartially cured, the gel fraction of the film 40 for the backside of asemiconductor is not especially limited. The gel fraction can beappropriately selected from a range of 50% by weight or less (0 to 50%by weight), preferably 30% by weight or less (Oto 30% by weight), andespecially preferably 10% by weight or less (0 to 10% by weight). Thegel fraction of the film for the backside of a semiconductor can bemeasured by the following method.

<Method of Measuring Gel Fraction>

About 0.1 g of a sample (sample weight) is precisely weighed from thefilm for the backside of a semiconductor, the sample is wrapped with amesh sheet, and then the sample is immersed in about 50 ml of toluene atroom temperature for a week. After that, the portion insoluble in thesolvent (content of the mesh sheet) is taken out of toluene and dried at130° C. for about 2 hours, and after drying, the portion insoluble inthe solvent is weighed (weight after immersion and drying), and the gelfraction (% by weight) is calculated from the following formula (a).

Gel fraction (% by weight)=[(Weight after immersion and drying)/(Sampleweight)]×100   (a)

The gel fraction of the film for the backside of a semiconductor can becontrolled by the type and the content of the resin component, the typeand the content of the crosslinking agent, the heating temperature, theheating time, and the like.

When the film for the backside of a semiconductor in the presentinvention is a filmthat is formed with a resin composition containing athermosetting resin such as an epoxy resin, adhesion to a semiconductorwafer can be exhibited effectively.

The tensile storage modulus at 23° C. of the uncured film 40 for thebackside of a semiconductor is preferably 1 GPa or more (1 to 50 GPa,for example), more preferably 2 GPa or more, and especially preferably 3GPa or more. When the tensile storage modulus is 1 GPa or more, adhesionof the film for the backside of a semiconductor to a support can beeffectively suppressed or prevented when a semiconductor chip is peeledfrom the pressure-sensitive adhesive layer 22 of a dicing tape togetherwith the film 40 for the backside of a semiconductor and the film 40 forthe backside of a semiconductor mounted on the support are transported.Examples of the support include a top tape and a bottom tape of acarrier tape.

The tensile storage modulus (23° C.) in the uncured portion of the filmfor the backside of a semiconductor can be controlled by the type andthe content of the resin component (a thermoplastic resin and athermosetting resin), the type and the content of the filler such as asilica filler, and the like.

When the film 40 for the backside of a semiconductor is a laminated filmin which a plurality of layers are laminated (when the film for thebackside of a semiconductor has a form of laminated layers), an exampleof the form of laminated layers includes a form of laminated layersconsisting of a wafer adhesion layer (a layer containing no coloringagent) and a laser marking layer (a layer containing no coloring agent).Other layers such as an intermediate layer, a light beam shieldinglayer, a reinforcing layer, a coloring agent layer, a base layer, anelectromagnetic wave shielding layer, a heat conducting layer, and apressure-sensitive adhesive layer may be provided between the waferadhesion layer and the laser marking layer. The wafer adhesion layer isa layer having excellent adhesion (tackiness) to a wafer and contactingwith the backside of the wafer. The laser marking layer is a layerhaving an excellent laser marking property and is used to perform lasermarking on the backside of a semiconductor chip.

The uncured films 40 for the backside of a semiconductor was producedwithout laminating the films on the dicing tape 2, and the tensilestorage modulus was measured using a dynamic viscoelasticity measurementapparatus (Solid Analyzer RS A2) manufactured by Rheometric ScientificFE, Ltd. in tensile mode, sample width 10 mm, sample length 22.5 mm,sample thickness 0.2 mm, frequency 1 Hz, temperature rise rate 10°C./min, under a nitrogen atmosphere, and at a prescribed temperature(23° C.).

The film 40 for the backside of a semiconductor is preferably protectedby a separator (a release liner, not shown in the drawings). Theseparator has a function of protecting the film for the backside of asemiconductor as a protective material until the film is used. Theseparator is peeled when pasting the semiconductor wafer onto the filmfor the backside of a semiconductor. Examples of the separator includepolyethylene, polypropylene, a plastic film such as polyethyleneterephthalate whose surface is coated with a release agent such as afluorine release agent or a long chain alkylacrylate release agent,andpaper. The separator can be formed by a conventionally known method.The thickness of the separator is also not especially limited.

The light transmittance (visible light transmittance) of visible light(having a wavelength of 400 to 800 nm) in the film 40 for the backsideof a semiconductor is not especially limited, and is preferably in arange of 20% or less (0 to 20%), more preferably 10% or less (0 to 10%),and especially preferably 5% or less (0 to 5%). When the visible lighttransmittance of the film 40 for the backside of a semiconductor islarger than 20%, there is a fear that a bad influence may be given tothe semiconductor element when the light beam passes. The visible lighttransmittance (%) can be controlled by the type and the content of theresin component of the film 40 for the backside of a semiconductor, thetype and the content of the coloring agent such as a pigment or a dye,the content of the inorganic filler, and the like.

The visible light transmittance (%) of the film for the backside of asemiconductor can be measured as follows. That is, a film for thebackside of a semiconductor having a thickness (average thickness) of 20μm is produced. The film for the backside of a semiconductor is thenirradiated with visible light having a wavelength of 400 to 800 nm (avisible light generator “Absorption Spectro Photometer” manufactured byShimadzu Corporation) at a prescribed intensity, and the intensity ofthe transmitted visible light beam is measured. The visible lighttransmittance can be obtained from a change of the intensity before andafter the visible light beam transmits through the film for the backsideof a semiconductor. It is also possible to obtain the visible lighttransmittance (%; wavelength: 400 to 800 nm) of the film for thebackside of a semiconductor having a thickness of 20 μm from the visiblelight transmittance (%; wavelength: 400 to 800 nm) of the film for thebackside of a semiconductor whose thickness is not 20 μm. The visiblelight transmittance (%) of the film for the backside of a semiconductorhaving a thickness of 20 μm is obtained in the present invention.However, the thickness of the film for the backside of a semiconductoraccording to the present invention is not limited to 20 μm.

The coefficient of moisture absorption of the film 40 for the backsideof a semiconductor is preferably low. Specifically, the coefficient ofmoisture absorption is preferably 1% by weight or less, and morepreferably 0.8% by weight or less . By making the coefficient ofmoisture absorption 1% by weight or less, the laser marking property canbe improved. Further, generation of voids between the film 40 for thebackside of a semiconductor and the semiconductor element can besuppressed or prevented in a reflow step, for example. The coefficientof moisture absorption is a value calculated from the weight changebefore and after the film 40 for the backside of a semiconductor areleft under an atmosphere of a temperature of 85° C. and a relativehumidity of 85% RH for 168 hours . When the film 40 for the backside ofa semiconductor are formed of a resin composition containing athermosetting resin, the coefficient of moisture absorption is a valueobtained the films for the backside of a semiconductor after thermalcuring are left under an atmosphere of a temperature of 85° C. and arelative humidity of 85% RH for 168 hours. The coefficient of moistureabsorption can be adjusted by changing the added amount of the inorganicfiller, for example.

The ratio of the volatile component of the film 40 for the backside of asemiconductor is preferably small. Specifically, the weight decreaserate (ratio of the weight decrease amount) of the film 40 for thebackside of a semiconductor after a heat treatment is preferably 1% byweight or less, and more preferably 0.8% by weight or less. Thecondition of the heating treatment is a heating temperature of 250° C.and a heating time of 1 hour, for example. By making the weight decreaserate 1% by weight or less, the laser marking property can be improved.The generation of cracks in the flip-chip type semiconductor device canbe suppressed or prevented in a reflow step, for example . The weightdecrease rate can be adjusted by adding an inorganic substance that candecrease the generation of cracks during a lead free solder reflow, forexample. When the film 40 for the backside of a semiconductor is formedwith a resin composition containing a thermosetting resin, the weightdecrease rate means a value obtained when the film for the backside of asemiconductor after thermal curing is heated under conditions of aheating temperature of 250° C. and a heating time of 1 hour.

The thickness of the film 40 for the backside of a semiconductor is notespecially limited. However, it can be appropriately selected from arange of about 2 μm to 200 μm. The thickness is preferably about 4 μm to160 μm, more preferably about 6 μm to 100 μm, and especially preferablyabout 10 μm to 80 μm.

(Dicing Tape)

The dicing tape 2 has a configuration in which the pressure-sensitiveadhesive layer 22 is formed on the base 21. As described above, thedicing tape may have a configuration in which the base 21 and thepressure-sensitive adhesive layer 22 are laminated. The base can be usedas a support base body of the pressure-sensitive adhesive layer, and thelike. The base 21 preferably has radiation transparency. Examples of thebase 21 include appropriate thin materials including paper bases such aspaper; fiber bases such as cloth, unwoven cloth, felt, and net; metalbases such as a metal foil and a metal plate; plastic bases such as aplastic film and sheet; rubber bases such as a rubber sheet; foams suchas a foamed sheet, and laminated bodies of these (especially laminatedbodies of a plastic base and other bases and laminated bodies of plasticfilms or sheets). In the present invention, a plastic base such as aplastic film or sheet can be preferably used as the base. Examples ofthe material of such a plastic base include olefin resins such aspolyethylene (PE), polypropylene (PP), and an ethylene-propylenecopolymer; copolymers having ethylene as a monomer component such as aethylene vinyl acetate copolymer (EVA), an ionomer resin, aethylene-(meth)acrylate copolymer, and an ethylene-(meth)acrylate(random, alternating) copolymer; polyesters such as polyethyleneterephthalate (PET), polyethylene naphthalate (PEN), and polybutyleneterephthalate (PBT); an acrylic resin; polyvinyl chloride (PVC);polyurethane; polycarbonate; polyphenylene sulfide (PPS); amide resinssuch as polyamide (nylon) and fully aromatic polyamide (aramid);polyether ether ketone (PEEK); polyimide; polyetherimide; polyvinylidenechloride; ABS (acrylonitrile-butadiene-styrene copolymer); a celluloseresin; a silicone resin; and a fluororesin.

Further, the material of the base 21 includes a polymer such as across-linked body of the above resins. The above plastic film may bealso used unstreched, or may be also used on which a monoaxial or abiaxial stretching treatment is performed depending on necessity.According to resin sheets in which heat shrinkable properties are givenby the stretching treatment, etc., the adhesive area of thepressure-sensitive adhesive layer 22 and the film 40 for the backside ofa semiconductor are reduced by thermally shrinking the base 21 afterdicing, and the recovery of the semiconductor chips (a semiconductorelement) can be facilitated.

A known surface treatment such as a chemical or physical treatment suchas a chromate treatment, ozone exposure, flame exposure, high voltageelectric exposure, and an ionized ultraviolet treatment, and a coatingtreatment by an undercoating agent (for example, a tacky substancedescribed later) can be performed on the surface of the base 21 in orderto improve adhesiveness, holding properties, etc. with the adjacentlayer.

The same type or different types can be appropriately selected and usedas the base 21, and several types can be blended and used as necessary.A vapor deposited layer of a conductive substance having a thickness ofabout 30 to 500 Å consisting of metals, alloys, and oxides of these canbe provided on the base 21 to give an antistatic function to the base21. The base 21 may be a single layer or a multilayer consisting of twotypes or more layers.

The thickness of the base 21 (total thickness in the case of a laminatedbody) is not especially limited, and can be appropriately selectedaccording to the strength, flexibility, purpose of use, and the like.For example, the thickness is generally 1000 μm or less (1 to 1000 μm,for example), preferably 10 to 500 μm, more preferably 20 to 300 μm, andespecially preferably about 30 to 200 μm. However, the thickness is notlimited to these ranges.

The base 21 may contain various additives such as a coloring agent, afiller, a plasticizer, an anti-aging agent, an antioxidant, asurfactant, and a flame retardant as long as the effects of the presentinvention are not deteriorated.

The pressure-sensitive adhesive layer 22 is formed with apressure-sensitive adhesive, and has adherability. Thepressure-sensitive adhesive is not especially limited, and can beappropriately selected among known pressure-sensitive adhesives.Specifically, known pressure-sensitive adhesives (refer to JapanesePatent Application Laid-Open Nos. 56-61468, 61-174857, 63-17981, and56-13040, for example) such as a pressure-sensitive adhesive having theabove-described characteristics can be appropriately selected from anacrylic pressure-sensitive adhesive, a rubber pressure-sensitiveadhesive, a vinylalkylether pressure-sensitive adhesive, a siliconepressure-sensitive adhesive, a polyester pressure-sensitive adhesive, apolyamide pressure-sensitive adhesive, a urethane pressure-sensitiveadhesive, a fluorine pressure-sensitive adhesive, a styrene-diene blockcopolymer pressure-sensitive adhesive, and a creep property improvedpressure-sensitive adhesive in which a hot-melt resin having a meltingpoint of about 200° C. or less is compounded in these pressure-sensitiveadhesives. A radiation curing type pressure-sensitive adhesive (or anenergy ray curing type pressure-sensitive adhesive) and a thermallyexpandable pressure-sensitive adhesive can also be used as thepressure-sensitive adhesive. The pressure-sensitive adhesives can beused alone or two types or more can be used together.

An acrylic pressure-sensitive adhesive and a rubber pressure-sensitiveadhesive can be suitably used as the pressure-sensitive adhesive, andespecially an acrylic pressure-sensitive adhesive is suitable. Anexample of the acrylic pressure-sensitive adhesive is an acrylicpressure-sensitive adhesive having an acrylic polymer, in which one typeor two types or more of alkyl(meth)acrylates are used as a monomercomponent, as a base polymer.

Examples of alkyl(meth)acrylates in the acrylic pressure-sensitiveadhesive include methyl(meth)acrylate, ethyl(meth)acrylate,propyl(meth)acrylate, isopropyl(meth)acrylate,butyl(meth)acrylate,isobutyl(meth)acrylate, s-butyl(meth)acrylate,t-butyl(meth)acrylate, pentyl(meth)acrylate, hexyl(meth)acrylate,heptyl(meth)acrylate, octyl(meth)acrylate, 2-ethylhexyl(meth)acrylate,isooctyl(meth)acrylate, nonyl(meth)acrylate,isononyl(meth)acrylate,decyl(meth)acrylate, isodecyl(meth)acrylate, undecyl(meth)acrylate,dodecyl(meth)acrylate, tridecyl(meth)acrylate, tetradecyl(meth)acrylate,pentadecyl(meth)acrylate, hexadecyl(meth)acrylate,heptadecyl(meth)acrylate, octadecyl(meth)acrylate,nonadecyl(meth)acrylate, and eicosyl(meth)acrylate. Alkyl(meth)acrylateshaving an alkyl group of 4 to 18 carbon atoms is suitable. The alkylgroup of alkyl(meth)acrylates may be any of linear or branched chain.

The acrylic polymer may contain units that correspond to other monomercomponents that is copolymerizable with alkyl(meth)acrylates describedabove (copolymerizable monomer component) for reforming cohesivestrength, heat resistance, and crosslinking property, as necessary.Examples of such copolymerizable monomer components include carboxylgroup-containing monomers such as (meth)acrylic acid (acrylic acid,methacrylic acid), carboxyethyl acrylate, carboxypentyl acrylate,itaconic acid, maleic acid, fumaric acid, and crotonic acid; acidanhydride group-containing monomers such as maleic anhydride anditaconic anhydride; hydroxyl group-containing monomers such ashydroxyethyl(meth)acrylate, hydroxypropyl(meth)acrylate,hydroxybutyl(meth)acrylate, hydroxyhexyl(meth)acrylate,hydroxyoctyl(meth)acrylate, hydroxydecyl(meth)acrylate,hydroxylauryl(meth)acrylate, and (4-hydroxymethylcyclohexyl)methylmethacrylate; sulfonate group-containing monomers such asstyrenesulfonic acid, allylsulfonic acid,2-(meth)acrylamide-2-methylpropanesulfonic acid,(meth)acrylamidepropanesulfonic acid, sulfopropyl(meth)acrylate, and(meth)acryloyloxynaphthalenesulfonic acid; phosphate group-containingmonomers such as 2-hydroxyethylacryloylphosphate; (N-substituted) amidemonomers such as (meth)acrylamide, N,N-dimethyl(meth)acrylamide,N-butyl(meth)acrylamide, N-methylol(meth)acrylamide, andN-methylolpropane(meth)acrylamide; aminoalkyl(meth)acrylate monomerssuch as aminoethyl(meth)acrylate, N,N-dimethlaminoethyl(meth)acrylate,and t-butylaminoethyl(meth)acrylate; alkoxyalkyl(meth)acrylate monomerssuch as methoxyethyl(meth)acrylate and ethoxyethyl(meth)acrylate;cyanoacrylate monomers such as acrylonitrile and methacrylonitrile;epoxy group-containing acrylic monomers such as glycidyl(meth)acrylate;styrene monomers such as styrene and a-methylstyrene; vinylestermonomers such as vinyl acetate andvinyl propionate; olefin monomers suchas isoprene, butadiene, and isobutylene; vinylether monomers such asvinylether; nitrogen-containing monomers such as N-vinylpyrrolidone,methylvinylpyrrolidone, vinylpyridine, vinylpiperidone,vinylpyrimidine,vinylpiperazine, vinylpyrazine, vinylpyrrole,vinylimidazole, vinyloxazole, vinylmorpholine, N-vinylcarboxylic acidamides, and N-vinylcaprolactam; maleimide monomers such asN-cyclohexylmaleimide, N-isopropylmaleimide, N-laurylmaleimide, andN-phenylmaleimide; itaconimide monomers such as N-methylitaconimide,N-ethylitaconimide, N-butylitaconimide, N-octylitaconimide,N-2-ethylhexylitaconimide,N-cyclohexylitaconimide,andN-laurylitaconimide;succinimide monomers suchas N-(meth)acryloyloxymethylene succinimide,N-(meth)acryloyl-6-oxyhexamethylene succinimide, andN-(meth)acryloyl-8-oxyoctamethylene succinimide; glycol acrylestermonomers such as polyethylene glycol(meth)acrylate, polypropyleneglycol(meth)acrylate, metoxyethylene glycol(meth)acrylate,andmetoxypolypropylene glycol(meth)acrylate; acrylate monomers having aheterocyclic ring, a halogen atom, a silicon atom, and the like such astetrahydrofurfuryl(meth)acrylate, fluorine(meth)acrylate, andsilicone(meth)acrylate; and polyfunctional monomers such as hexanedioldi(meth)acrylate, (poly)ethylene glycol di(meth)acrylate,(poly)propylene glycol di(meth)acrylate, neopentyl glycoldi(meth)acrylate, pentaerythritol di(meth)acrylate, trimethylolpropanetri(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritolhexa(meth)acrylate, epoxyacrylate, polyesteracrylate, urethaneacrylate,divinylbenzene, butyl di(meth)acrylate, and hexyl di(meth)acrylate. Onetype or two types or more of these copolymerizable monomer componentscan be used.

As described above, the base polymer constituting the pressure-sensitiveadhesive layer 22 (for example, the acrylic polymer) preferably has theSP value (SP2) of 13 to 7, and more preferably has the SP value (SP2) of12 to 8 as long as a relationship of (SP1)>(SP2) is satisfied. When thebase polymer having the SP value (SP2) of 13 or less is used, a largedifference between the SP value (SP2) and the SP value (SP1) of thethermoplastic resin contained in the film 40 for the backside of asemiconductor can be easily obtained.

The SP value (SP2) of the base polymer constituting thepressure-sensitive adhesive layer 22 can be controlled by appropriatelyselecting the monomer components when the pressure-sensitive adhesivelayer 22 is formed.

When a radiation curing type pressure-sensitive adhesive (or an energyray curing type pressure-sensitive adhesive) is used as thepressure-sensitive adhesive, examples of the radiation curing typepressure-sensitive adhesive (composition) include an internal radiationcuring type pressure-sensitive adhesive having a polymer with a radicalreactive carbon-carbon double bond in the polymer side chain, the mainchain, or the ends of the main chain as a base polymer and a radiationcuring type pressure-sensitive adhesive in which ultraviolet-raycuring-type monomer component and oligomer component are compounded inthe pressure-sensitive adhesive. When a thermally expandablepressure-sensitive adhesive is used as the pressure-sensitive adhesive,examples thereof include a thermally expandable pressure-sensitiveadhesive containing a pressure-sensitive adhesive and a foaming agent(especially, a thermally expandable microsphere).

The pressure-sensitive adhesive layer 22 of the present invention maycontain various additives such as a tackifier, a coloring agent, athickener, an extender, a filler, a plasticizer, an anti-aging agent, anantioxidant, a surfactant, and a crosslinking agent as long as theeffects of the present invention are not deteriorated.

The crosslinking agent is not especially limited, and known crosslinkingagents can be used. Specific examples of the crosslinking agent includean isocyanate crosslinking agent, an epoxy crosslinking agent, amelamine crosslinking agent, a peroxide crosslinking agent, a ureacrosslinking agent, a metal alkoxide crosslinking agent, a metal chelatecrosslinking agent, a metal salt crosslinking agent, a carbodiimidecrosslinking agent, an oxazoline crosslinking agent, an aziridinecrosslinking agent, and an amine crosslinking agent, and an isocyanatecrosslinking agent and an epoxy crosslinking agent are preferable. Thecrosslinking agents can be used alone or two types or more can be usedtogether. The used amount of the crosslinking agent is not especiallylimited.

Examples of the isocyanate crosslinking agent include lower aliphaticpolyisocyanates such as 1,2-ethylene diisocyanate,1,4-butylenediisocyanate, and 1,6-hexamethylene diisocyanate;alicyclicpolyisocyanates such as cyclopentylene diisocyanate,cyclohexylene diisocyanate, isophorone diisocyanate, hydrogenatedtolylene diisocyanate, and hydrogenated xylene diisocyanate; andaromatic polyisocyanates such as 2,4-tolylene diisocyanate, 2,6-tolylenediisocyanate, 4, 4′-diphenylmethane diisocyanate, and xylylenediisocyanate. A trimethylolpropane/tolylene diisocyanate trimeric adduct(Coronate L manufactured by Nippon Polyurethane Industry Co., Ltd.), anda trimethylolpropane/hexamethylene diisocyanate trimeric adduct(Coronate HL manufactured by Nippon Polyurethane Industry Co., Ltd.) canalso be used. Examples of the epoxy crosslinking agent includeN,N,N′,N′-tetraglycidyl-m-xylenediamine, diglycidylaniline,1,3-bis(N,N-glycidylaminomethyl)cyclohexane, 1,6-hexanedioldiglycidylether, neopentylglycol diglycidylether, ethyleneglycoldiglycidylether, propyleneglycol diglycidylether, polyethyleneglycoldiglycidylether, polypropyleneglycol diglycidylether, sorbitolpolyglycidylether, glycerol polyglycidylether, pentaerithritolpolyglycidylether, polyglycerol polyglycidylether, sorbitanpolyglycidylether, trimethylolpropane polyglycidylether, diglycidyladipate, o-diglycidyl phthalate,triglycidyl-tris(2-hydroxyethyl)isocyanurate, resorcin diglycidylether,bisphenol-S-diglycidylether; and an epoxy resin having two or more epoxygroups in a molecule.

In the present invention, a crosslinking treatment can be performed byirradiation with an electron beam, an ultraviolet ray, or the likeinstead of using the crosslinking agent or in addition to the use of thecrosslinking agent.

The pressure-sensitive adhesive layer 22 can be formed by a commonmethod of forming a sheet-like layer by mixing the pressure-sensitiveadhesive with a solvent, other additives, and the like as necessary.Specifically, the pressure-sensitive adhesive layer 22 can be producedby a method of applying the pressure-sensitive adhesive or a mixturecontaining the pressure-sensitive adhesive, a solvent and otheradditives to the base 21, a method of forming the pressure-sensitiveadhesive layer 22 by applying the above-described mixture to anappropriate separator (release paper, for example), and transferring(adhering) the resultant onto the base 21, for example.

The thickness of the pressure-sensitive adhesive layer 22 is notespecially limited, and is about 5 to 300 μm (preferably 5 to 200 μm,more preferably 5 to 100 μm, and especially preferably 7 to 50 μm). Whenthe thickness of the pressure-sensitive adhesive layer 22 is in theabove-described range, adequate adhesive power can be exhibited. Thepressure-sensitive adhesive layer 22 may be a single layer or aplurality of layers.

The difference between the surface free energy E1 of the film 40 for thebackside of a semiconductor and the surface free energy E2 of thepressure-sensitive adhesive layer 22 (E1-E2) is preferably 10 mJ/m² ormore, more preferably 15 mJ/m² or more, and further preferably 20 mJ/m²or more. When the difference (E1-E2) is 10 mJ/m² or more, peeling can beeasily performed.

The rate of change in a beam transmittance is preferably 30 or less andmore preferably 20 or less that can be obtained using the followingformula from the beam transmittance at 532 nm of the dicing tape 2 whenthe dicing-tape integrated film 1 for the backside of a semiconductor isleft as it is at 23° C. for 1 hour and then the film 40 for the backsideof a semiconductor is peeled from the dicing tape 2 at the interface,and the beam transmittance at 532 nm of the dicing tape 2 when thedicing-tape integrated film 1 for the backside of a semiconductor isleft as it is at 100° C. for 1 hour and then the film 40 for thebackside of a semiconductor is peeled fromthe dicing tape 2 at theinterface . A small rate of change in a beam transmittance means that adecrease of the transmittance is small. That is, it means that transferof the coloring agent to the pressure-sensitive adhesive layer of thedicing tape is less by heating.

(Rate of change in a transmittance)=[1−(Transmittance after heating at100° C. for 1 hour)/(Transmittance before heating)]×100 (%)

In the present invention, an antistatic function can be given to thedicing-Tape Integrated Film 1 for Backside of Semiconductor. With thisconfiguration, generation of static electricity on the films duringadhesion and peeling and damages of the circuit due to electrificationof the semiconductor wafer, and the like can be prevented. Theantistatic function can be given by an appropriate method such as amethod of adding an antistatic agent or a conductive substance to thebase 21, the pressure-sensitive adhesive layer 22, or the film 40 forthe backside of a flip-chip type semiconductor and a method of providinga conductive layer made of a charge-transfer complex or a metal film tothe base 21. A method of giving the antistatic function is preferablewith which impurity ions that can deteriorate the semiconductor waferare hardly generated. Examples of the conductive substance (conductivefiller) that is compounded to give electric conductivity and to improveheat conductivity include spherical, needle-like, and flaky metalpowders of silver, aluminum, gold, copper, nickel, and conductivealloys, metal oxides of alumina, amorphous carbon black, and graphite.However, the film 40 for the backside of a flip-chip type semiconductorare preferably electrically non-conductive from the viewpoint of makingthe films have no electrical leakage.

The dicing-Tape Integrated Film 1 for Backside of Semiconductor may beformed in a form in which the films are wound into a roll or a form inwhich the films are laminated. When the films have a form in which theyare wound into a roll, a dicing tape-integrated film for the backside ofa semiconductor having a form in which the films are wound into a rollcan be produced by winding a laminated body of the film for the backsideof a flip-chip type semiconductor and the dicing tape into a roll whileprotecting the film or the laminated body with a separator as necessary.The dicing-Tape Integrated Film 1 for Backside of Semiconductor that iswound into a roll may be configured with the base 21, thepressure-sensitive adhesive layer 22 that is formed on one side of thebase 21, the film 40 for the backside of a semiconductor that is formedon the pressure-sensitive adhesive layer 22, and a release treatmentlayer (a back treatment layer) that is formed on the other surface ofthe base 21.

The thickness of the dicing-Tape Integrated Film 1 for Backside ofSemiconductor (total thickness of the film for the backside of asemiconductor and the dicing tape consisting of the base 21 and thepressure-sensitive adhesive layer 22) can be selected from a range of 7to 11300 μm, and is preferably 17 to 1600 μm, and more preferably 28 to1200 μm.

By controlling the ratio between the thickness of the film for thebackside of a flip-chip type semiconductor and the thickness of thepressure-sensitive adhesive layer of the dicing tape and the ratiobetween the thickness of the film for the backside of a flip-chip typesemiconductor and the thickness of the dicing tape (total thickness ofthe base and the pressure-sensitive adhesive layer) in the dicingtape-integrated film for the backside of a semiconductor, the dicingproperty in a dicing step, the pickup property in a pickup step, and thelike can be improved, and the dicing tape-integrated film for thebackside of a semiconductor can be effectively used from the dicing stepof a semiconductor wafer to the flip-chip bonding step of asemiconductor chip.

(Method of Manufacturing Dicing Tape-Integrated Film for the Backside ofSemiconductor)

A method of manufacturing the dicing tape-integrated film for thebackside of a semiconductor according to this embodiment is explainedusing the dicing-Tape Integrated Film 1 for Backside of Semiconductorshown in FIG. 1 as an example. First, the base 21 can be formed by aconventionally known film forming method. Examples of the film formingmethod include a calender film forming method, a casting method in anorganic solvent, an inflation extrusion method in a closed system, a Tdie extrusion method, a co-extrusion method, and a dry laminatingmethod.

The pressure-sensitive adhesive layer 22 is formed by applying apressure-sensitive adhesive composition to the base 21 and drying thecomposition (by crosslinking by heat as necessary). Examples of theapplication method include roll coating, screen coating, and gravurecoating. The pressure-sensitive adhesive layer 22 may be formed on thebase 21 by applying the pressure-sensitive adhesive composition directlyto the base 21, or the pressure-sensitive adhesive layer 22 may betransferred to the base 21 after the pressure-sensitive adhesive layer22 is formed by applying the pressure-sensitive adhesive composition toa release paper whose surface has been subjected to a release treatment.With this configuration, the dicing tape 2 is produced in which thepressure-sensitive adhesive layer 22 is formed on the base 21.

On the other hand, a formation material for forming the film 40 for thebackside of a semiconductor is applied onto release paper so that thethickness after drying becomes prescribed thickness, and then, it isdried under a prescribed condition (drying by carrying out a heatingtreatment when thermal curing is necessary, etc.) to form a coatinglayer. This coating layer is transferred onto the pressure-sensitiveadhesive layer 22 to form the film 40 for the backside of asemiconductor on the pressure-sensitive adhesive layer 22. Further, aformation material for forming the film 40 for the backside of asemiconductor is applied directly onto the pressure-sensitive adhesivelayer 22, and it is dried under a prescribed condition (drying bycarrying out a heating treatment when thermal curing is necessary, etc.)also to form the film 40 for the backside of a semiconductor on thepressure-sensitive adhesive layer 22. with this, the dicing-tapeintegrated film 1 for the backside of a semiconductor according to thepresent invention can be obtained. When thermal curing is performed toform the film 40 for the backside of a semiconductor, it is important toperform thermal curing up to a level at which the film is partiallycured. However, it is preferable not to perform thermal curing.

The dicing-Tape Integrated Film 1 for Backside of Semiconductor can beused suitably in the manufacture of a semiconductor device having aflip-chip connecting step. The dicing-Tape Integrated Film 1 forBackside of Semiconductor of the present invention is used tomanufacture a flip-chip mounted semiconductor device, and the flip-chipmounted semiconductor device is manufactured in a form in which the film40 for the backside of a semiconductor of the dicing-Tape IntegratedFilm 1 for Backside of Semiconductor is pasted to the backside of thesemiconductor chip. Therefore, the dicing-Tape Integrated Film 1 forBackside of Semiconductor of the present invention can be used for aflip-chip mounted semiconductor device (a semiconductor device in a formin which the semiconductor chip is fixed to an adherend such as asubstrate by a flip-chip bonding method).

(Semiconductor Wafer)

The semiconductor wafer is not especially limited as long as it is aknown or common semiconductor wafer, and semiconductor wafers made ofvarious materials can be appropriately selected and used. In the presentinvention, a silicon wafer can be suitably used as the semiconductorwafer.

(Method of Manufacturing Semiconductor Device)

In the following, the method of manufacturing a semiconductor deviceaccording to this embodiment is explained by referring to FIG. 2. FIG. 2is a sectional schematic drawing showing a method of manufacturing asemiconductor device using the dicing-Tape Integrated Film 1 forBackside of Semiconductor .

The method of manufacturing a semiconductor device according to thepresent embodiment at least has

a step A of pasting a semiconductor wafer on the film 40 for thebackside of a semiconductor in the dicing-tape integrated film 1 for thebackside of a semiconductor,

a step B of performing laser marking to the film 40 for the backside ofa semiconductor from the dicing tape 2 side after the step A,

a step C of dicing the semiconductor wafer to form a semiconductorelement,

a step D of peeling the semiconductor element from thepressure-sensitive adhesive layer 22 together with the film 40 for thebackside of a semiconductor, and

a step E of flip-chip bonding the semiconductor element on an adherend.

[Mounting Step]

As shown in FIG. 2( a), the separator that is appropriately provided onthe film 40 for the backside of a semiconductor of the dicing-TapeIntegrated Film 1 for Backside of Semiconductor is appropriately peeledoff, a semiconductor wafer 4 is pasted to the film 40 for the backsideof a semiconductor, and the laminate is fixed by adhering and holding(step A). At this time, the film 40 for the backside of a semiconductoris uncured (including a condition of being partially cured). Thedicing-Tape Integrated Film 1 for Backside of Semiconductor is pasted tothe backside of the semiconductor wafer 4. The backside of thesemiconductor wafer 4 means the surface opposite to the circuit surface(also referred to as a non-circuit surface or a non-electrode formingsurface). The pasting method is not especially limited, and a pastingmethod by pressure-bonding is preferable. The pressure-bonding isperformed by pressing by a pressing means such as a press roll.

Next, baking (heating) is performed as necessary in order to firmly fixthe film 40 for the backside of a semiconductor to a semiconductor wafer4. This baking is performed at 80° C. to 150° C. for 0.1 hour to 24hours for example.

[Laser Marking Step]

Next, as shown in FIG. 2( b), laser marking is performed on the film 40for the backside of a semiconductor using a laser 36 for laser markingfrom the dicing tape 2 side (step B). The condition of laser marking isnot especially limited. However, it is preferable to irradiate the film40 for the backside of a semiconductor with a laser beam [wavelength:532 nm] having the intensity of 0.3 W to 2.0 W. Further, it ispreferable to irradiate so that the process depth (depth) becomes 2 μmor more. The upper limit of the process depth is not especially limited.However, it can be selected from a range of 2 μm to 25 μm, it ispreferably 3 μm or more (3 μm to 20 μm), and more preferably 5 μm ormore (5 μm to 15 μm). The condition of laser marking is set to be withinthe above-described ranges to exhibit excellent laser markingproperties.

In the present embodiment, a coloring agent having relatively highpolarity in which its solubility to toluene at 23° C. is 2 g/100 ml orless is contained to the film 40 for the backside of a semiconductorhaving high polarity (SP value). Because of that, the transfer of thecoloring agent onto the pressure-sensitive adhesive layer 22 by heatingsuch as the baking step is suppressed. As a result, a problem hardlyoccurs in which the laser beam is blocked by the coloring agenttransferred to the dicing tape 2, the laser beam does not reach to thefilm 40 for the backside of a semiconductor, and laser marking cannot beperformed well, even when the laser beam was irradiated from the dicingtape 2 side.

Further, the laser processing properties of the film 40 for the backsideof a semiconductor can be controlled by the types and the content of theconstituting resin components, the type and the content of the coloringagent, the type and the content of the crosslinking agent, the type andthe content of the filler, etc.

[Dicing Step]

As shown in FIG. 2( c), dicing of the semiconductor wafer 4 isperformed. With this operation, the semiconductor wafer 4 is cut intoindividual pieces (cut into small pieces) having a prescribed size, anda semiconductor chip 5 is manufactured (step C). The dicing is performedfrom the circuit surface side of the semiconductor wafer 4 by a normalmethod, for example. For example, a cutting method called full cut inwhich cutting is performed up to the dicing-Tape Integrated Film 1 forBackside of Semiconductor can be adopted in this step. The dicingapparatus used in this step is not especially limited, and aconventionally known apparatus can be used. Because the semiconductorwafer 4 is adhered and fixed with excellent adhesion by the dicing-TapeIntegrated Film 1 for Backside of Semiconductor having the film for thebackside of a semiconductor, chip cracks and chip fly can be suppressedand damages to the semiconductor wafer 4 can also be suppressed.

When expanding the dicing-Tape Integrated Film 1 for Backside ofSemiconductor, a conventionally known expanding apparatus can be used.The expanding apparatus has a donut-shaped outer ring that can push downthe dicing-Tape Integrated Film 1 for Backside of Semiconductor througha dicing ring and an inner ring that has a smaller diameter than theouter ring and that supports the dicing tape-integrated film for thebackside of a semiconductor. With this expanding step, generation ofdamages caused by the contact between adjacent semiconductor chips canbe prevented in the pickup step described later.

[Pickup Step]

The semiconductor chip 5 is peeled from the dicing tape 2 together withthe film 40 for the backside of a semiconductor by performing pickup ofthe semiconductor chip 5 as shown in FIG. 2( d) to collect thesemiconductor chip 5 that is adhered and fixed to the dicing-TapeIntegrated Film 1 for Backside of Semiconductor (step D). The pickupmethod is not especially limited, and various conventionally knownmethods can be adopted. An example of the method is a method of pushingup an individual semiconductor chip 5 from the side of the base 21 ofthe dicing-Tape Integrated Film 1 for Backside of Semiconductor with aneedle and picking up the pushed semiconductor chip 5 with a pickupapparatus.

When a radiation curing type pressure-sensitive adhesive (or an energybeam curing type pressure-sensitive adhesive) is used as thepressure-sensitive adhesive constituting the pressure-sensitive adhesivelayer 22, it is preferably to irradiate the layer with an ultravioletray to perform pickup. With this, pickup can be performed easily.Especially, in the laser marking step, air bubbles may be generated atthe interface between the film 40 for the backside of a semiconductorand the pressure-sensitive adhesive layer 22. Because of that, aradiation curing type pressure-sensitive adhesive (or an energy beamcuring type pressure-sensitive adhesive) is used as thepressure-sensitive adhesive constituting the pressure-sensitive adhesivelayer 22, the pressure-sensitive adhesive layer 22 and the film 40 forthe backside of a semiconductor are firmly pasted together in the lasermarking step to suppress the generation of air bubbles. Then, it ispreferable to irradiate the layer with radiation (or an energy beam) tolower the adhesive power and to perform pickup easily during pickup.

The backside of the semiconductor chip 5 that is picked up is protectedby the film 40 for the backside of a semiconductor .

[Flip-Chip Connecting Step]

As shown in FIG. 2( e), the semiconductor chip 5 that is picked up isfixed to an adherend such as a substrate by a flip-chip bonding method(flip-chip mounting method) (step E). Specifically, the semiconductorchip 5 is fixed to an adherend 6 by a normal method in a form that thecircuit surface (also referred to as the surface, a circuit patternforming surface, or an electrode forming surface) of the semiconductorchip 5 faces the adherend 6. The semiconductor chip 5 can be fixed tothe adherend 6 while securing electrical conduction of the semiconductorchip 5 with the adherend 6 by contacting and pressing a bump 51 formedon the circuit surface side of the semiconductor chip 5 to a conductivematerial 61 such as solder for bonding that is adhered to a connectionpad of the adherend 6 andmelting the conductive material (a flip-chipbonding step). At this time, a space is formed between the semiconductorchip 5 and the adherend 6, and the distance of the space is generallyabout 30 to 300 μm. After flip-chip bonding (flip-chip connection) ofthe semiconductor chip 5 onto the adherend 6, it is important to washthe facing surface and the space between the semiconductor chip 5 to theadherend 6 and to seal the space by filling the space with a sealingmaterial such as a sealing resin.

Various substrates such as a lead frame and a circuit board (a wiringcircuit board, for example) can be used as the adherend 6. The materialof the substrate is not especially limited, and examples thereof includea ceramic substrate and a plastic substrate. Examples of the plasticsubstrate include an epoxy substrate, a bismaleimide triazine substrate,and a polyimide substrate.

The material of the bump and the conductive material in the flip-chipbonding step are not especially limited, and examples thereof includesolders (alloys) of a tin-lead metal material, a tin-silver metalmaterial, a tin-silver-copper metal material, a tin-zincmetal material,and a tin-zinc-bismuth metal material, a gold metal material, and acopper metal material.

In the flip-chip bonding step, the bump of the circuit surface side ofthe semiconductor chip 5 and the conductive material on the surface ofthe adherend 6 are connected by melting the conductive material. Thetemperature when the conductive material is molten is normally about260° C. (250 to 300° C., for example). The dicing tape-integrated filmfor the backside of a semiconductor of the present invention can haveheat resistance so that it can resist a high temperature in theflip-chip bonding step by forming the film for the backside of asemiconductor with an epoxy resin, or the like.

In this step, the facing surface (an electrode forming surface) and thespace between the semiconductor chip 5 and the adherend 6 are preferablywashed. The washing liquid that is used in washing is not especiallylimited, and examples thereof include an organic washing liquid and awater washing liquid. The film for the backside of a semiconductor inthe dicing tape-integrated film for the backside of a semiconductor ofthe present invention has solvent resistance to the washing liquid, anddoes not substantially have solubility in these washing liquids. Becauseof that, various washing liquids can be used as the washing liquid, andwashing can be performed by a conventional method without requiring aspecial washing liquid.

Next, a sealing step is performed to seal the space between theflip-chip bonded semiconductor chip 5 and the adherend 6. The sealingstep is performed using a sealing resin . The sealing condition is notespecially limited. Thermal curing (reflow) of the sealing resin isperformed normally by heating the sealing resin at 175° C. for 60 to 90seconds. However, the present invention is not limited to this, andcuring can be performed at 165 to 185° C. for a few minutes, forexample. In the heat process of this step, thermal curing of not onlythe sealing resin but also the film 40 for the backside of asemiconductor may be performed at the same time. In this case, it is notnecessary to newly add a step for thermally curing the film 40 for thebackside of a semiconductor. However, the present invention is notlimited to this example, a step of thermally curing the film 40 for thebackside of a semiconductor may be performed separately before thesealing resin is thermally cured.

The sealing resin is not especially limited as long as it is a resinhaving insulation properties, and can be appropriately selected fromsealing materials such as a known sealing resin. However, an insulatingresin having elasticity is preferable. Examples of the sealing resininclude a resin composition containing an epoxy resin. Examples of theepoxy resin include epoxy resins described above. The sealing resin witha resin composition containing an epoxy resin may contain athermosetting resin such as a phenol resin other than the epoxy resin, athermoplastic resin, and the like as a resin component besides the epoxyresin. The phenol resin can also be used as a curing agent for the epoxyresin, and examples of the phenol resin include the above-describedphenol resins.

In the above-described embodiment, a case is explained in which thespace between a semiconductor chip 5 and an adherend 6 is sealed byfilling the space with liquid sealant (a sealing resin, etc.). However,the present invention is not limited to this example, and a sheet resincomposition may be used. As the method of sealing the space between thesemiconductor chip and the adherend using a sheet rein composition,conventionally known methods described in JP-A-2001-332520, etc. canbeadopted. Therefore, the detailed explanation of the method is omitted.

After the sealing step is performed, a heat treatment (a reflow stepthat is performed after laser marking) may be performed as necessary.The condition of the heat treatment is not especially limited, and theheat treatment can be performed according to the standards by JEDECSolid State Technology Association. For example, the heat treatment canbe performed at a temperature (upper limit) of 210 to 270° C. and aperiod of 5 to 50 seconds. With this step, a semiconductor package canbe mounted on a substrate such as a mother board.

Because the semiconductor device that is manufactured using the dicingtape-integrated film for the backside of a semiconductor of the presentinvention is a semiconductor device that is mounted by a flip-chipmounting method, the semiconductor device has a shape thinner andsmaller than a semiconductor device that is mounted by a die bondingmounting method. Because of this, the semiconductor device can besuitably used as various electronic apparatuses and electronic parts ormaterials and members thereof. Specific examples of the electronicapparatus in which the flip-chip mounted semiconductor device of thepresent invention can be used include a portable phone, PHS, a smallcomputer such as PDA (personal digital assistant), a notebook personalcomputer, Netbook (trademark), or a wearable computer, a smallelectronic apparatus in which a portable phone and a computer areintegrated, Digital Camera (trademark), a digital video camera, a smalltelevision, a small game machine, a small digital audio player, anelectronic organizer, an electronic dictionary, an electronic apparatusterminal for an electronic book, and a mobile electronic apparatus(portable electronic apparatus) such as a small digital type clock orwatch. Examples of the electronic apparatus also include an electronicapparatus other than a mobile type apparatus (i.e., a stationaryapparatus) such as a desktop personal computer, a flat-panel television,an electronic apparatus for recording and playing such as a hard discrecorder or a DVD player, a projector, or a micromachine. Examples ofthe electronic parts or materials and members of the electronicapparatus and electronic parts include a component of CPU and componentsof various recording apparatuses such as a memory and a hard disk.

The case in which an electromagnetic wave shielding layer 31 is a singlelayer was explained in the above-described embodiment. However, theelectromagnetic wave shielding layer is not limited to a single layerand it may be two or more layers in the present invention. When theelectromagnetic wave shielding layer has two or more layers, the layerconfiguration is not especially limited. For example, a plurality ofelectromagnetic wave shielding layers may be laminated without otherlayers interposed therebetween, or a plurality of electromagnetic waveshielding layers may be laminated with other layers (adhesive layers forexample) interposed therebetween. When the electromagnetic waveshielding layer has two or more layers, the electromagnetic wave can beattenuated by one electromagnetic wave shielding layer first and furtherattenuated by other electromagnetic wave shielding layers.

EXAMPLES Example 1

<Production of the Film for the Backside of a Semiconductor>

To 100 parts of an acrylic ester based polymer (Paracron W-197CM, SPvalue 12, manufactured by Negami Chemical Industrial Co., Ltd.) havingethylacrylate as a main component, 113 parts of an epoxy resin (Epicoat1004, manufactured by Japan Epoxy Resins Co., Ltd.), 121 parts of aphenol resin (MEH-7851H, manufactured by Meiwa Plastic Industries,Ltd.), 246 parts of spherical silica (SO-25R, manufactured by ADMATECHSCo., Ltd.), and 5 parts of dye (OIL BLACK SOM-L-0543, manufactured byOrient Chemical Industries Co., Ltd.) were dissolved in methyethylketoneto prepare an adhesive composition solution having a concentration ofsolid content of 23.6% by weight.

This adhesive composition solution was applied onto a release-treatedfilm consisting of a silicon release-treated polyethyleneterephthalatefilm having a thickness of 50 μm as a release liner, and dried at 130°C. for 2 minutes to form a film A for the backside of a semiconductorhaving a thickness of 20 μm.

“OIL BLACK SOM-L-0543” is a dye having an anthraquinone skeleton.

<Production of the Dicing Tape>

In a reactor having a cooling tube, a nitrogen gas introducing tube, athermometer, and a stirrer, 86.4 parts of 2-ethylhexyl acrylate(referred to as “2EHA” below), 13.6 parts of 2-hydroxylethyl acrylate(referred to as “HEA” below), 0.2 part of benzoyl peroxide, and 65 partsof toluene were placed and a polymerization process was performed in anitrogen gas flow at 61° C. for 6 hours to obtain an acrylic polymer A.

To the acrylic polymer A, 14.6 parts of 2-methacryloyloxyethylisocyanate(referred to as “MOI” below) was added, and an addition reaction processwas performed in an air flow at 50° C. for 48 hours to obtain an acrylicpolymer A′.

Then, to 100 parts of the acrylic polymer A′, 8 parts of apolyisocyanate compound (a trade name “Coronate L”, manufactured byNippon Polyurethane Industry Co., Ltd.) and 5 parts of aphotopolymerization initiator (a trade name “Irgacure 651”, manufacturedby Chiba Specialty Chemicals Inc.) were added to obtain apressure-sensitive adhesive composition solution A.

The pressure-sensitive adhesive composition solution A was applied tothe surface of a PET release liner in which a silicone treatment wasperformed, and heated and dried at 120° C. for 2 minutes to form apressure-sensitive adhesive layer having a thickness of 10 μm. Then, apolyolefin film was pasted onto the pressure-sensitive adhesive layerthat was formed. The thickness of this polyolefin film is 100 μm, and aprinting layer that blocks radiation and was formed on a portioncorresponding to the frame pasting region was formed in advance. Afterthat, a crosslinking treatment was performed by heating at 50° C. for 24hours to produce a dicing tape A. The SP value of the acrylic polymerused in the pressure-sensitive adhesive layer was 10.4.

<Dicing-Tape Integrated Film for the Backside of a Semiconductor>

The film A for the backside of a semiconductor was pasted onto thepressure-sensitive adhesive layer of the dicing tape A that was producedusing a hand roller to produce the dicing-tape integrated film A for thebackside of a semiconductor according to Example 1.

Example 2

<Production of the Film for the Backside of a Semiconductor>

The film B for the backside of a semiconductor according to Example 2was produced in the same way as Example 1 except “ORIPACS B-1”(manufactured by Orient Chemical Industries Co., Ltd.) was used as acoloring agent instead of “OIL BLACK SOM-L-0543” (manufactured by OrientChemical Industries Co., Ltd.) “ORIPACS B-1” is a dye having a chromiumcomplex.

<Dicing-Tape Integrated Film for the Backside of a Semiconductor>

The film B for the backside of a semiconductor was pasted onto thepressure-sensitive adhesive layer of the dicing tape A that was producedin Example 1 using a hand roller to produce the dicing-tape integratedfilm B for the backside of a semiconductor according to Example 2.

Example 3

<Production of the Film for the Backside of a Semiconductor>

The film C for the backside of a semiconductor according to Example 3was produced in the same way as Example 1 except “SDO-7” (manufacturedby Orient Chemical Industries Co., Ltd.) was used as a coloring agentinstead of “OIL BLACK SOM-L-0543” (manufactured by Orient ChemicalIndustries Co., Ltd.) “SDO-7” is a dye having an anthraquinone skeleton.

<Dicing-Tape Integrated Film for the Backside of a Semiconductor>

The film C for the backside of a semiconductor was pasted onto thepressure-sensitive adhesive layer of the dicing tape A that was producedin Example 1 using a hand roller to produce the dicing-tape integratedfilm C for the backside of a semiconductor according to Example 3.

Example 4

<Production of the Film for the Backside of a Semiconductor>

The film D for the backside of a semiconductor according to Example 4was produced in the same way as Example 1 except “Carbon Black #47”(manufactured by Mitsubishi Chemical Corporation) was used as thecoloring agent instead of “OIL BLACK SOM-L-0543” (manufactured by OrientChemical Industries Co., Ltd.)

<Dicing-Tape Integrated Film for the Backside of a Semiconductor>

The film D for the backside of a semiconductor was pasted onto thepressure-sensitive adhesive layer of the dicing tape A that was producedin Example 1 using a hand roller to produce the dicing-tape integratedfilm D for the backside of a semiconductor according to Example 4.

Comparative Example 1

<Production of the Film for the Backside of a Semiconductor>

The film E for the backside of a semiconductor according to ComparativeExample 1 was produced in the same way as Example 1 except “OIL BLACKHBB” (manufactured by Orient Chemical Industries Co., Ltd.) was used asthe coloring agent instead of “OIL BLACK SOM-L-0543” (manufactured byOrient Chemical Industries Co., Ltd.)

<Dicing-Tape Integrated Film for the Backside of a Semiconductor>

The film E for the backside of a semiconductor was pasted onto thepressure-sensitive adhesive layer of the dicing tape A that was producedin Example 1 using a hand roller to produce the dicing-tape integratedfilm E for the backside of a semiconductor according to ComparativeExample 1.

Comparative Example 2

<Production of the Film for the Backside of a Semiconductor>

The film F for the backside of a semiconductor according to ComparativeExample 2 was produced in the same way as Example 1 except “OIL BLACKB-31” (manufactured by Orient Chemical Industries Co., Ltd.) was used asthe coloring agent instead of “OIL BLACK SOM-L-0543” (manufactured byOrient Chemical Industries Co., Ltd.)

<Dicing-Tape Integrated Film for the Backside of a Semiconductor>

The film F for the backside of a semiconductor was pasted onto thepressure-sensitive adhesive layer of the dicing tape A that was producedin Example 1 using a hand roller to produce the dicing-tape integratedfilm F for the backside of a semiconductor according to ComparativeExample 2.

(Measurement of the Solubility of the Coloring Agent to Toluene at 23°C.)

To 100 ml of a toluene solvent, 50 g of the coloring agent was added, itwas stirred at room temperature (23° C.) for 30 minutes using a stirrerbar, filtration was performed, and the filtered solid content was driedat 120° C. for 1 hour to measure the weight. The decreased amount fromthe added amount (50 g) was made to be the solubility to toluene. Theresult is shown in Table 1.

(Measurement of the Rate of Change in Transmittance of the Dicing tape)

The produced dicing-tape integrated film for the backside of asemiconductor was left as it was at 23° C. for 1 hour, and the dicingtape was peeled from the film for the backside of a semiconductor at theinterface. After that, the beam transmittance of the dicing tape at 532nm was measured. This was made to be “the transmittance before heating”.

Then, the produced dicing-tape integrated film for the backside of asemiconductor was left as it was at 100° C. for 1 hour, and the dicingtape was peeled from the film for the backside of a semiconductor at theinterface. After that, the beam transmittance of the dicing tape at 532nm was measured. This was made to be “the transmittance after heating at100° C. for 1 hour”.

After that, “the rate of change in transmittance” was obtained using thefollowing formula. The result is shown in Table 1.

(Rate of change in a transmittance)=[1-(Transmittance after heating at100° C. for 1 hour)/(Transmittance before heating)]×100 (%)

(Measurement of the Surface Free Energy)

The produced dicing-tape integrated film for the backside of asemiconductor was peeled at the interface of the dicing tape and thefilm for the backside of a semiconductor. After that, the surface freeenergy E1 of the film for the backside of a semiconductor and thesurface free energy E2 of the pressure-sensitive adhesive layer of thedicing tape were obtained. Specifically, contact angles of water andiodomethane were measured using a contact angle gauge, and each surfacefree energy value was calculated from the contact angles with ageometric mean method. The result is shown in Table 1. The difference(E1-E2) is also shown in Table 1.

TABLE 1 Example Example Example Example Comparative Comparative 1 2 3 4Example 1 Example 2 Solubility (g/100 ml) of 0.5 or 0.5 or 1.9 0 28 5.1Coloring Agent to Toluene less less Rate of Change in 6 3 18 1 97 59Transmittance (%) Surface Free Energy E1 38 38 39 38 39 38 (mJ/m²)Surface Free Energy E2 18 18 18 18 18 18 (mJ/m²) Difference (E1 − E2) 2020 21 20 21 20 (mJ/m²)

The rate of change in transmittance is large in the comparative examplesin which the coloring agent was used having high solubility to tolueneat 23° C. This means that the transmittance was largely decreased. Thatis, it means that the coloring agent transferred to thepressure-sensitive adhesive layer of the dicing tape by heating.

EXPLANATION OF REFERENCE NUMERALS

1 Dicing-TapeIntegratedFilmforBacksideofSemiconductor

2 Dicing Tape

21 Substrate

22 Pressure-Sensitive Adhesive Layer

23 Portion Corresponding to Pasting Portion of Semiconductor Wafer

40 Film for Backside of Semiconductor (Film for Backside of Flip-ChipSemiconductor)

4 Semiconductor Wafer

5 Semiconductor Chip

51 Bump Formed on Circuit Surface Side of Semiconductor Chip 5

6 Adherend

61 Conductive Material for Bonding Adhered to Connection Pad of Adherend6

What is claimed is:
 1. A dicing-tape integrated film for a backside of asemiconductor having a dicing tape having a substrate and apressure-sensitive adhesive layer formed on the substrate and a film fora backside of a flip-chip semiconductor formed on the pressure-sensitiveadhesive layer of the dicing tape, wherein the film for the backside ofa flip-chip semiconductor contains a coloring agent, and the solubilityof the coloring agent to toluene at 23° C. is 2 g/100 ml or less.
 2. Thedicing-tape integrated film for the backside of a semiconductoraccording to claim 1, wherein the coloring agent has an anthraquinoneskeleton.
 3. The dicing-tape integrated film for the backside of asemiconductor according to claim 1, wherein a difference between surfacefree energy E1 of the film for the backside of a flip-chip semiconductorand surface free energy E2 of the pressure-sensitive adhesive layer(E1-E2) is 10 mJ/m² or more.
 4. A method of manufacturing asemiconductor device using the dicing-tape integrated film for thebackside of a semiconductor according to claim 1 having a step A ofpasting a semiconductor wafer on a film for the backside of a flip-chipsemiconductor in the dicing-tape integrated film for the backside of asemiconductor, a step B of performing laser marking to the film for thebackside of a flip-chip semiconductor from the dicing tape side afterthe step A, a step C of dicing the semiconductor wafer to form asemiconductor element, a step D of peeling the semiconductor elementfrom the pressure-sensitive adhesive layer together with the film forthe backside of a flip-chip semiconductor, and a step E of flip-chipbonding the semiconductor element on an adherend.
 5. A semiconductordevice manufactured using the dicing-tape integrated film for thebackside of a semiconductor according to claim 1.